This is elementary but still I see this over looked time and time again. A vacant home needs to have the utilites on! Gas could be an issue and as long as it is not the only heating system then that is fine to have it off during the colder months and definalty off during the warmer months. The thermostate should be set so the home is confortable when the potential buyer/tenant enters the home. Remember first impressions are lasting impressions. If the home is inviting and comfortable people can begin to see themselves living there. The home should create a feeling of comfort as soon as they walk in the door. A few little extras you can do that cost next to nothing are things like keep toilet paper on the holders in each bathroom and add a throw rug and hand towel to each bathroom. It's nice to have a basket in the kitchen with papertowels, mints and your contact info. To go that extra mile you could have bottles of water in the frig with a sign saying help yourself, make yourself at home!. Go ahead and give them the feeling of home so when they tour the next location and that person does not have anything special for them, your home will have the lasting impression!